The field of the disclosure relates generally to gas turbines and, more particularly, to evacuation devices, or vents for gaseous fuel powering the gas turbines.
At least some known gas turbines are powered by a gaseous fuel routed through a supply circuit. The gaseous fuel supply circuit generally used to regulate a flow and a pressure of gaseous fuel that powers the gas turbine and used to ensure rapid security of the circuit. To achieve such rapid security, the supply circuit comprises several valves fitted in series on fuel routing pipes of the gaseous fuel supply circuit.
In cases where emergency shutdown of the system is required, such as a case of detection of gas leakage or excess speed of the gas turbine, the gaseous fuel supply circuit must be drained within a very short period, preferably within 30 seconds, to obtain a residual pressure in the closed circuit substantially equal to the atmospheric pressure. The residual gaseous fuel in the supply circuit is then released to the atmosphere.
Furthermore, during turbine startup, it is also necessary to supply the turbine with a gaseous fuel having a temperature greater than a determined value to obtain the conditions required in the combustion chamber to be able to start the turbine. For this purpose, the supply circuit comprises one or more heating devices capable of gradually increasing the gaseous fuel temperature while being routed towards the combustion chamber. However, if the gaseous fuel has not reached the desired temperature, it cannot power the combustion chamber, and is generally released to the atmosphere.
However, the discharge of gaseous fuel to the atmosphere has several disadvantages such as from an environmental point of view (i.e., toxicity of gaseous fuel), and from a security point of view. The volume of gaseous fuel released to the atmosphere may be difficult to disperse due to the large volume released, a density of gaseous fuel, or topography of the site where the gaseous fuel is released.
JP document 08200650 discloses a gaseous fuel routing device comprising one vent that releases the gaseous fuel.